Bitcoin is going to lead to travel restrictions in the future. TSA doesn’t exist to keep you safe on planes. It exists for the same reason the Great Wall of China was built. To keep tax payers in. To make sure you don’t leave the country with cash or gold.
Now imagine if you had an invisible pocket. You can put anything you want in that pocket and no TSA agent can see what’s in it or even know you have the pocket. What does the state do then? First they will try to restrict movement, but eventually they will see its futile and start competing to keep resources within their jurisdiction.
That’s how we get to the sovereign individual thesis, but in the mean time be prepared for harassment.